How many miles did it take to notice improved fuel efficiency?

[King-max]

I purchased my 2015 SE C-Max in late November 2015.  I currently have close to 6000 km on it.  I am averaging 5.8 L/100km and it is in winter driving conditions here in Canada.  At what mileage (km) have you noticed an increased fuel efficiency due to break-in?  I understand that temperature plays a big part but does it take up to 5,000 - 10,000 km to see enhanced economy?

[ptjones]

I would think you have gone enough km, but the car does take a pretty big hit in the winter. Here is some info that explains it.  There are things you can do to improve your MPG's. :)

 

Paul

[BIG ROCCO]

I think we're at ~ 3,500 miles on our C-Max, and I noticed the fuel mileage increasing lately.  The temps in Phoenix have also been increasing lately - it's been in the 70s and 80s.  So, I don't know if we are experiencing break in or if it's the temps or maybe a little of both.  I think I have seen posts in the past that said full break in does not occur until 10K or 20K miles.  On my Buick Lacrosse mild hybrid, it did seem like fuel mileage did gradually get better up until 20K miles

[rjam]

I had a 2013 SEL and now have a 2015 SEL that now has 3000 miles on it. I live in Oregon. Tamps low 40's to low 50's. The mileage around town 43 avg. Same now as the day I bought it. Don't know if that helps. :)

[scottwood2]

Mine did get a little better over time but it was not a major change.  Warm weather will help a lot but driving style does even more so.   10 mile trip to work this morning at 10 deg was about 42 MPG.  Warm weather can get 50 to 60 mpg for this same route.   Best MPG for this was 77 MPG.   Major city route that takes about 30 min. 

 

Hope that helps.

[plus 3 golfer]

King-max, virtually all of your engine break-in should be complete at 6000 km.   I can't say there was improvement in my FE that I can attribute to "break-in" but there might be some in the first 1000 miles or so.   My first fill-up was at around 150 miles so that I could begin recording "my" FE.(car had 79 miles on it when purchased with dealer fill up).  So, given that engine tolerances are better today than decades ago and some factory run / test time is on the engine,  break-in is not what it used to be (several thousands of miles maybe up to 10k miles).

 

It seems to me that your 5.8 L/100km (40.6 mpg) is pretty good for Ontario in the winter if your trips are short (cold engine), use the heater, and have no grille covers.

 

BOTTOM LINE:  Don't hold your breath waiting for additional break-in to increase your FE.  If you want to increase FE, be pro-active in taking steps that should increase FE.

 

For reference, on my current tank I have 74.9 miles and averaging 45.1 mpg on the trip gauge in suburban, hilly driving between 2-5 miles one way several times a day with ambient temperatures ranging from 20*F to 35*F.  I have grille covers and don't use the HVAC heater on these trips.  I do use the seat heater.  On these short suburban trips ICE coolant temp will seldom be above 140*F.  In addition to this suburban driving, I will likely make several trips on the interstates of around 50+ mile round trips.at around 70 mph average   FE on these trips will likely average around 37/40 mpg depending on ambient temperature.  I will use the HVAC heater as ICE coolant temp will generally run between 185*F-205*F and up to 230*F when going up longer grades at 70+ mph with grille covers.  Without the grille covers, the coolant temps would be considerably less since the grille shutters will begin to open around 192*F.    I do watch / record data via ForScan and grille shutters begin to open around 192*F+ and are fully open at 212-214*F.  Higher coolant temperature generally means more efficient ICE operation.  Decreasing air flow through the engine compartment generally decreases aerodynamic drag.

 

With 800 miles on my C-Max, I ran tests at 70 mph with and without grille covers with ambient temperature around 27*F.   See the link as my results support Paul's graph.

Edited February 11, 2016 by Plus 3 Golfer

[fbov]

...Don't hold your breath waiting for additional break-in to increase your FE.  If you want to increase FE, be pro-active in taking steps that should increase FE....

+1

 

There are three things you can do that have been proven to reduce the car's fuel consumption:

- grill block

- block heater

- good fuel

 

Here's some data, for a car with grill blocks, but no block heaters, on snow tires (Thanksgiving to Easter). This is a "rural route" with 12 lights and 6 Stop signs, but very little traffic, allowing great freedom in when to use ICE and how fast to go. Trip time is held constant. Data is shown for all of 2014 , with 2015 data split by the type of fuel used. I did this in June/July with very similar results.

Summer fuel comparison, shift from 54.7 to 58.7 MPG, roughly constant temperature.

Winter fuel comparison, 3-4 MPG shift, greater at higher temperature.

 

I can't control the weather, but I can choose to use high-octane fuel, and avoid ethanol. That's still no guarantee, as the driver remains the major determinant of the car's mileage.

 

Have fun,

Frank

[King-max]

Thank you for the many replies.  I didn't realize that the fuel grade made such a difference.  Here in Ontario we mainly have 10% ethanol in the low grade fuel.  Problem is that here in Canada there is a 10 - 12 cent per litre difference in 87 grade vs. 91 grade which translates into approximately 50 cents per gallon difference.  Any fuel economy increase with better fuel actually means I would pay more money than if I filled up with the 87 grade including the ethanol addition.

[stevedebi]

Thank you for the many replies.  I didn't realize that the fuel grade made such a difference.  Here in Ontario we mainly have 10% ethanol in the low grade fuel.  Problem is that here in Canada there is a 10 - 12 cent per litre difference in 87 grade vs. 91 grade which translates into approximately 50 cents per gallon difference.  Any fuel economy increase with better fuel actually means I would pay more money than if I filled up with the 87 grade including the ethanol addition.

I don't think the C-Max is rated for 91. They recommend 87 minimum. I would not run 91 in mine.

[fbov]

...Any fuel economy increase with better fuel actually means I would pay more money than if I filled up with the 87 grade including the ethanol addition.

I didn't mean to suggest that you'd save money on the deal, just that it has a positive effect if you're driving style allows. I don't see any difference in highway driving.

 

And I know of no vehicle ever made that could be damaged by using premium. Steve's right when he says 87 is a minimum, as you can destroy an engine with pre-ignition. I'm doing this for the knowledge; never know when I might need to get an extra 10% out of a tank. Plus, Paul's got all the bragging rights sewn up!

 

HAve fun,

Frank

[ptjones]

I run 93 octane all the time in GA, it  isn't  cost effective with gas so cheap now, but it was close at $4. I hate to give up 2 mpg to go to 87 octane. ;) Ethanol Free is worth another 1 mpg, but too expensive. :)

 

Paul

[stevedebi]

I run 93 octane all the time in GA, it  isn't  cost effective with gas so cheap now, but it was close at $4. I hate to give up 2 mpg to go to 87 octane. ;) Ethanol Free is worth another 1 mpg, but too expensive. :)

 

Paul

Paul,

Interesting to know. You are the only person I've read of that uses premium. Some cars are programmed to adjust timing to match the octane, I had not realized the C-Max was one of those (it isn't in the owner manual).

 

Well, it made me look at the OM again. They specifically mention Octane levels below 87 at high altitudes, and say not to use it.

[ptjones]

Paul,

Interesting to know. You are the only person I've read of that uses premium. Some cars are programmed to adjust timing to match the octane, I had not realized the C-Max was one of those (it isn't in the owner manual).

 

Well, it made me look at the OM again. They specifically mention Octane levels below 87 at high altitudes, and say not to use it.

There are atleast several including Jus-A-CMax,  I think all members that have gotten 800+ miles on a tank do.  I believe all FORD's  have knock sensors and will advance the timing until knocking is detected, then back off a little.  I first noticed this with my first AeroStar Van in 86, had problems with ICE knocking when it warmed up.  Chevron was the only gas it wouldn't knock on. Using Premium also solved the problem and increased my range by 20+ miles when towing a trailer, which is a big deal when driving in the Southwest. I also notice this with MADMAX and the ScanGaugeII you could see the ECM advancing the timing more with Premium than Regular. :)

 

Paul

[ScubaDadMiami]

Count me in on the group using premium. It does help a little.

 

The other thing that really made about a 3+ MPG difference (for around town driving speeds, less for highway) for me was switching to 0W20 oil. My dealer charged a big premium for using this oil, and I decided to go without it at my 20,000 mile service, and I am really losing out since switching back to the standard factory spec oil.

 

As far as break in and fuel economy improvement goes, I noticed an improvement at about 12,000 miles.

Edited March 5, 2016 by ScubaDadMiami

[Kelleytoons]

I actually noticed an improvement with around 11K miles, and I suspect it's the battery (as others have noted, the engine machining is so good nowadays that you don't need to "break in" an engine for very long anymore.  But batteries do take a while to adjust to the best charge/discharge cycles, AFAIK).  It actually surprised me since I felt it couldn't get much better (IOW, I was very happy with what I was getting -- I seem to be getting the same mileage I was getting when I was *very* careful, even though I am much less so nowadays.  Sorry -- just cheaper gas doesn't make me as good a hypermiler <g>).

 

On that subject: if I have been using 87 grade gas for so long and switch now to premium am I at any risk to damage to the Max?  I am really happy with what I'm getting and all, but the idea of getting more per tank interests me (and gas IS so cheap it's a good time to experiment).  What are pros and cons of doing so?

[raadsel]

I actually noticed an improvement with around 11K miles, and I suspect it's the battery (as others have noted, the engine machining is so good nowadays that you don't need to "break in" an engine for very long anymore.  But batteries do take a while to adjust to the best charge/discharge cycles, AFAIK).  It actually surprised me since I felt it couldn't get much better (IOW, I was very happy with what I was getting -- I seem to be getting the same mileage I was getting when I was *very* careful, even though I am much less so nowadays.  Sorry -- just cheaper gas doesn't make me as good a hypermiler <g>).

 

On that subject: if I have been using 87 grade gas for so long and switch now to premium am I at any risk to damage to the Max?  I am really happy with what I'm getting and all, but the idea of getting more per tank interests me (and gas IS so cheap it's a good time to experiment).  What are pros and cons of doing so?

 

I just don't see the advantage of using Premium. While it does appear that it will slightly improve fuel economy, I'd lose more money buying the premium gas than I save with the improved fuel economy. It would appear, based on my last tank, I'd pay about 42 cents a gallon more, but only save about 10 cents per gallon from the extra mpgs. If you want to experiment, I don't see where it would do any damage to your car. 

[fbov]

There is no way pump gas with increased octane can hurt the car. (The opposite is not true.) For the greatest effect, make it ethanol-free.

 

Then drive routes and speeds where you can get at least 2/3 EV, as that puts the ICE in the right operating mode to eek the most energy out of the fuel.

 

If you're driving routes and speeds that don't pull all the energy out of 87E10, you're not likely to see benefit from 91E0. For me, that's highway driving, 40% EV or so.

 

have fun,

Frank

 

And no, you'll never save money this way.

Edited March 5, 2016 by fbov

[plus 3 golfer]

....On that subject: if I have been using 87 grade gas for so long and switch now to premium am I at any risk to damage to the Max?  I am really happy with what I'm getting and all, but the idea of getting more per tank interests me (and gas IS so cheap it's a good time to experiment).  What are pros and cons of doing so?

But around here the difference between premium and regular is virtually the same ($0.40 per gallon) regardless of the base price of regular.  So, if regular is $1.60 / gallon, premium costs 25% more than regular.  At $4/gallon, premium would cost 10% more.  But, I'd experiment when the cost of gas is high not low as I'd lose less $$ experimenting when gas is more expensive. :)  

 

IMO, the pros of premium gas are lower emissions, using less of resource (crude oil), and likely slightly better performance.  The only con of using premium is value at current and likely price levels I'll see for as long as I own my C-Max.  :)      

[Thomas Walker]

From what I heard. If your car is built for 87- or 89-octane gas upgrading to premium won't do you any good. In fact, it could even harm both your car and the environment, since more unburned gas will get into the emissions system and interfere with its ability to prevent noxious discharge. That unburnt gas will drip out your tailpipe on the road and pollute the environment.

[plus 3 golfer]

From what I heard. If your car is built for 87- or 89-octane gas upgrading to premium won't do you any good. In fact, it could even harm both your car and the environment, since more unburned gas will get into the emissions system and interfere with its ability to prevent noxious discharge. That unburnt gas will drip out your tailpipe on the road and pollute the environment.

 

Modern cars are built to burn a minimum octane rated fuel as the cars adjust timing (retard for lower octane fuel and advance timing for higher octane fuel) and regulate the amount of fuel (short term and long term fuel trim) during closed loop operation to achieve a stoichiometric ratio (virtually all fuel is oxidized) as determined by the emissions and other monitoring systems. For example using regular grade gas, under hard acceleration up a steep hill, detonation may occur and will be detected by the knock sensor.  Timing will be retarded.  But using premium fuel under the same conditions, detonation may not occur or timing may not have to be retarded as much.  

 

Emissions using premium at worst should be the same as using regular. If you have a reference tor your statement please provide it. I have never seen a study that even hinted that premium fuel could harm a modern car or the environment. 

 

Because there will usually be a fuel saving using premium fuel (may not be an economic savings), the total emissions using premium fuel will be less.  

[MrGreen29]

I've only had my car for about 18 days. I've filled up once with half a tank and got 42.3 calculated and filled up a second time from near empty which was calculated at 39.2. I definitely know I have a ways to go. Hopefully i see some improvement when the weather warms up!

[RobMax]

From what I heard. If your car is built for 87- or 89-octane gas upgrading to premium won't do you any good. In fact, it could even harm both your car and the environment, since more unburned gas will get into the emissions system and interfere with its ability to prevent noxious discharge. That unburnt gas will drip out your tailpipe on the road and pollute the environment.

 

This myth needs to be dispelled. Octane rating is nothing more than a number to help differentiate how much compression the fuel can withstand before spontaneous combustion (aka uncontrolled explosion) in the cylinders occurs. The lower the number, the less compression it takes before 'boom' happens.

 

Good example: My Dad's old 71 F-100 pinged (aka experienced uncontrolled combustion events) on anything less than 91, even though the engine was built for 87. As it turned out, things got old from carbon build-up, gummed up rings, etc, and it caused uneven firing on decreased octane fuel, but it ran well on 91. No big deal. 

 

Modern vehicles also have knock sensors to help burn efficiently for different octane mixtures. Plus, you could dump a whole lot more unburned gas into the exhaust stream and modern emissions controls (i.e. catalysts) will cook off any excess hydrocarbons, CO, and NOX. There will be no "gas dripping out your tailpipe" unless you happen to have a fuel injector stuck open or some other major problem that the engine and/or emissions systems just couldn't compensate for.

Edited March 27, 2016 by RobMax